Prior art workers have devised a number of nail driving tools by which shingles such as asphalt shingles or the like may be affixed to a roof.
Nail driving tools for this purpose are generally provided with canister-type magazines adapted to contain fasteners (in this instance roofing nails) arranged in tandem in strips which are coiled. The canister-type magazine is generally preferred for this purpose since it increases the number of fasteners which can be accommodated by the magazine, as compared to the capacity of a typical linear magazine.
The nails of a strip are arranged and held in a tandem row by any appropriate coilable means. These means may constitute tape means, paper means, wire means, plastic means or the like, all of which are well known in the art.
The shingle elements are affixed to a roof in overlapping comes. It is therefore important that each shingle element be properly aligned with respect to the shingle element it overlaps. This is true not only from the standpoint of providing a truly protective roof, but also from a visual standpoint. For many years proper alignment of the shingle elements was accomplished through the use of separate gauging or measuring devices. In recent years, prior art workers have provided a shingle gauge located directly on the nail driving tool so that the tool can first be used as a measuring or gauging device, and thereafter as a nail driving device. To this end, the nail driving tool is provided with an adjustable gauge beneath its magazine and a locating surface adjacent the nose of the tool. The gauge is brought into abutting relationship with the lower edge of the previously installed shingle element. The next shingle element to be installed in overlapping relationship therewith is so located that its lower edge abuts the locating surface associated with the nose of the tool. This is done at at least two positions along the overlapping shingle element. Once the overlapping shingle element has been properly located, the tool can then be used to nail it in place.
The gauge mounted on the tool beneath the magazine is normally made adjustable in such a way that it may be shifted toward and away from the nose of the tool so as to increase or decrease the distance between the gauge abutment surface and the locating surface associated with the tool nose. In this way, shingle elements of different sizes can be properly located by the shingle gauge. In prior art structures, to adjust the gauge for the particular shingle elements being install, it was necessary to loosen one or more nut and bolt assemblies, shift the gauge to the proper position, and thereafter tighten the one or more nut and bolt assemblies while holding the gauge in adjusted position. This was both cumbersome and time consuming.
U.S. Pat. No. 5,267,682 is exemplary of those patents teaching a nail driving tool provided with an adjustable shingle gauge. Again, adjustment of the shingle gauge requires loosening of a bolt and nut assembly, shifting of the shingle gauge, and retightening of the bolt and nut assembly. In this instance, however, a nut and bolt loosening and tightening mechanism is provided, constituting an integral part of the gauge assembly. While this clearly represents an improvement over the prior art, it still is rather time consuming, necessitates considerable manipulation and requires that the gauge be held in the desired position until locked in place by the nut and bolt. The present invention is based upon the discovery of a quick adjustment system wherein a gauge is mount on a support located beneath the magazine of the nail driving tool and is slidable thereon toward and away from the tool nose. The gauge is fastened to a spring latch which has an upturned end receivable in any one a plurality of locking slots extending transversely of the support. The gauge is manually pivotable between locked and unlocked positions and, in unlocked position can be manually moved toward and away from the forward locating surface. Thereafter, the spring latch biases the gauge to its locked position in any selected one of the transverse locking slots. In this way, an incremental positive locking system for the gauge is provided. The gauge is also capable of being shifted with respect to the spring latch to provide a fine positioning adjustment to compensate for part wear and the like. The incremental positive locking system requires no tools, and no bolting or unbolting of elements. Locking in the desired position is immediate and the gauge does not have to be held in the desired position until locking is accomplished.